1. Field of the Invention
The present invention relates generally to round balers and, more particularly, to an improved bale wrapping mechanism that provides, among other things, improved feeding of the wrapper at the initiation of the wrapping cycle, which serves to eliminate many of the problems commonly associated with conventional wrapper mechanisms.
2. Discussion of Prior Art
An important, yet all too often problematic, part of baling operations involves wrapping of the bale once it has been formed. It has been determined that such problems are often attributable to the lightweight and flimsy nature of preferred wrapping materials. Particularly, movement of the wrapper from its source to the baling chamber is highly susceptible to being affected by factors such as wind, static electricity, etc. Although these factors may be relatively inconsequential to other baling operations, they have the potential of causing the wrapper to be misdirected or caught upon some part of the baler disposed along the wrapper path of travel. For example, even slight winds can blow the wrapper off course such that continued feeding of the wrapper will cause the wrapper to accumulate in undesirable areas.
It will be appreciated by those ordinarily skilled in the art that a significant number of conventional wrapper dispensing mechanisms are designed so that the wrapper is pulled from its source by the bale and/or the bale forming mechanism once the wrapper has been fed sufficiently toward or into the baling chamber. Accordingly, movement of the wrapper is positively controlled once it has been grasped by the bale and/or the bale forming mechanism, thereby reducing the likelihood of the above-noted problems. In most instances, however, the wrapper must initially travel some distance before being grasped by the bale and/or the bale forming mechanism. For example, wrapper dispensing mechanisms will often be spaced some distance from the baling chamber, such as along the rear wall of the baler. Consequently, most of these dispensing mechanisms include feed rollers for initially feeding the wrapper to the point at which it is grasped by the bale or bale forming mechanism.
Obviously, the speed of the feed rollers must be coordinated with the speed at which wrapper will be pulled by the bale and/or forming mechanism, otherwise, back-wrapping onto the feed rollers and various other problems may occur. In an attempt to resolve the problems associated with overfeeding or underfeeding of the wrapper by the feed rollers, one expedient suggests drivingly connecting the feed rollers to one of the bale forming rolls in such a manner that the feed rollers are rotated at a slower speed than the speed at which the forming mechanism will pull the wrapper from its source (for eliminating overfeeding problems), and providing the drive with an overrunning clutch that allows free rotation of the rollers when the wrapper is pulled by the forming mechanism at a speed faster than that at which the rollers are rotating (for eliminating underfeeding problems). Such an expedient is the subject of U.S. Pat. No. 5,729,953, issued Mar. 24, 1998, entitled Round Bale Wrapper Dispensing Apparatus, assigned of record to the assignee of the present application. Yet there is still an initial path along which the wrapper must travel before it is positively grasped by the bale and/or the bale forming mechanism. As with baler shown in the '953 patent, a majority of conventional wrapper dispensing mechanisms rely on the wrapper being fed by the rollers and guided by gravity along this initial path. However, as noted above, movement of the wrapper along this initial path may be adversely affected by various factors, such as the wind or static electricity. For example, untoward wind or static electricity may cause the wrapper to catch on the cutting mechanism or some other structure disposed along the initial path of the wrapper, whereby continued feeding of the wrapper by the feed rollers results in undesirable accumulation or back-wrapping onto the rollers.
Another problem associated with conventional wrapper dispensing mechanisms involves cutting the wrapper as the wrapping cycle is completed. Those ordinarily skilled in the art will appreciate that incomplete severance of the wrapper can result in lost time and material and, in some cases, damage to the baler. These problems are especially troublesome with common mesh-type wrappers formed of several intertwined strands, with each strand having the potential of unraveling or clumping together the entire web if left uncut at the end of the wrapping cycle. Many wrapping materials have tremendous resiliency and therefore require controlled cutting; otherwise, the wrapper may spring back into an uncontrollable mass or out of engagement with the feed rollers. In addition, when the cutter fails to make a clean cut of the wrapper, the unsevered portion of the wrapper may snag on the cutter and consequently obstruct movement of the wrapper toward the baling chamber.
Yet another recognized problem with conventional wrapper dispensing mechanisms involves loading new supplies of wrapping material. For example, the rolls of solid or mesh-type webs can be relatively heavy and unwieldy, however, these rolls are often housed within compartments on the baler that are inconvenient and difficult to access.